this is a 2oz mop, its 4" tall and as wide as the squeeze-e mop or the smash blitz marker. the nib writes 10mm lines (same nib on the drip mop) . its the best combination of size and ink capacity for a mop. yes, $10 is expensive for a 2oz mop but this is how you get the most out of your k-60:

buy the 5-pack of extra nibs (they're called "mini drip mop replacement nib") because they'll come in handy when you tear the nib going over a sharp little bump or whatever.

for refills. unless you want to keep paying $10 for a new marker every time you run out of ink, i think some kids actually do that and i think that's why kr doesn't make refill bottles. smash makes a perfect refill for this mop because k-60 colors and smash inks are very similar in both colors and thickness. for example, i bought a green k-60 a long time ago and i've been using smash's "teal legit" as a refill ever since.

so grab the 5-pack of replacement nibs and an 8oz of smash for refills and you'll be set.

good review! seen this? http://artprimo.com/catalog/art_primo_ap_mop_comparison_chart